The One Nation group will seek to "outride" for the Labour leader's ideas and demonstrate that the party has moved into a post-Blairite/Brownite era.

Newly appointed Labour shadow cabinet ministers Gloria de Piero, Tristram Hunt and Emma Reynolds take part in a photocall in London last week. Photograph: Getty Images.

Since Ed Miliband became Labour leader, many have noted the lack of an identifiable band of supporters to champion his ideas and defend him from attack. For fear of fracturing party unity after his narrow victory in 2010, Miliband avoided cultivating a political faction as Margaret Thatcher and Tony Blair did. "I am my own outrider", he has often privately remarked. It is an approach that has left him vulnerable to internal criticism, most notably last summer. One question frequently asked during those torrid weeks was "where are the Milibandites?"

Among the aims of last week's shadow cabinet reshuffle was to offer an answer. The Labour leader rewarded those who have engaged with his political and ideological project and who have shown consistent loyalty. It was notable that both Tristram Hunt (promoted to shadow education secretary) and Gloria De Piero (promoted to shadow minister for women and equalities) contributed chapters to the recent book One Nation: power, hope, community, regarded in the party as the founding text of the Milibandites (it was co-edited by two of his early supporters, Rachel Reeves and Owen Smith). Other contributors, such as Dan Jarvis, Rushanara Ali and Kate Green, were also promoted to more senior posts.

In an attempt to continue to give greater definition to Miliband's project, those involved in the book have now launched a formal One Nation group. The aim, one shadow cabinet minister told me, would be to "outride" for Miliband's ideas, to champion community politics (a central theme of the book) and to demonstrate that the party had moved into a "post-Blairite/Brownite era".

In its supportive stance towards Miliband, it is analogous to the Conservative 301 Group, the loyalist faction formed to act as a counterweight to the 1922 committee. The test of the group's success will be whether it can advance Miliband's project without merely being seen as a front for the leadership.